Entropy
by imafangirlforever
Summary: There is a reason why Yaoyorozu Momo never mentions her father. There is a reason why her mother is so strict. There is a reason why Momo avoids using her quirk outside of battle. A familiar face resurfaces, and Momo is forced to face her past.
1. Chapter 1

**Set directly after the cultural festival. Let's pretend that whatever happens next in the manga happens later, okay? ;)**

* * *

 _Cold. It was cold, much too cold. Bitter winter air nipped at her neck as she shivered, trying not to fidget. "Are we done, Papa?" she pleaded, tugging on his sleeve. It was chilly outside, and Momo wanted to go inside. But Momo was a good girl, so she didn't cry. It was hard to hold in her tears, though, while wearing nothing more than a bathing suit in December. "It's cold."_

 _He hardly spared her a glance. "Quit complaining and stop acting so petulantly, Yaomomo. You're doing this to help others. You want to be a hero, don't you?"_

" _But Papa—"_

" _Concentrate on the formulas, darling," he chided._

" _...please, Papa?"_

" _Just a few more, Yaomomo. A few more..."_

* * *

"Yaoyorozu."

Momo practically fell out of her seat, jerking upwards and letting out a small gasp. She blinked in surprise, taking in her surroundings before realizing that she was in the classroom. She had stayed after class to clean up, but she must have fallen asleep, for the classroom was only dimly illuminated by the dying rays of light that filtered through the window.

 _How long had I been sleeping for? Moreover..._

Pink dusted her cheeks. "M-my apologies, Todoroki-san," Momo stammered, bowing her head in apology. Self-consciously, she tugged at her ponytail, pursing her lips in annoyance when she realized her disheveled state. "I'm afraid I went to bed rather late last night. Is there something you need?"

The fire and ice user pinned her with a cool stare, tilting his head ever so slightly; she could vaguely detect the concern in his eyes. "Not really," he answered. His voice, calm and steady, was soothing, in a way. "I was returning from training and saw the lights were still on."

He didn't voice his concerns aloud, but Momo read his nonverbal cues well enough. It was a given, considering the months and months she spent sitting alongside her taciturn, laconic seatmate. "I'm fine, Todoroki-san," she reassured him, flashing him a bright smile. "Really. I was helping Jirou with something and stayed up a little too late."

That _was_ true: Momo had explained the day's lesson to Jirou over cups of hot chocolate the night before since Kaminari had distracted the headphones-user during a crucial part of the lecture. They had finally retired to bed around midnight, which was hardly late for Momo, but she was plagued by nightmares _(memories)_ for the rest of a very fitful night.

Todoroki looked somewhat unconvinced, but accepted her appeasement. "Are you heading to the dorms, then?"

"A-ah, I suppose I am."

"Mm."

"Why don't we walk back together?" Momo suggested, giggling nervously to cover up her anxiety. Todoroki was one of the people she admired the most, but it wasn't just for his looks or his insanely powerful Quirk: it was for his decisiveness, his intelligence, and his _kindness,_ which she had been lucky enough to experience herself. _Compared to him, I'm…_

A hand reached out and touched her shoulder. Momo nearly jumped out of her skin. "T-Todoroki-san?"

"Stop thinking, Yaoyorozu," he ordered.

"But—"

"Stop _thinking,"_ he stressed. She stared at him, bewildered. Something about her gaze must have unnerved him, for Todoroki glanced away. "You always have that look in your eyes when you think of depressing things," he mumbled uncomfortably, averting his eyes. "You're a capable leader and hero, Yaoyorozu. Stop putting yourself down."

A small smile stretched across her face as her eyes softened. _This_ was why Momo admired Todoroki Shouto so much.

"You're much too kind, Todoroki-san," she replied. Suddenly, looking at him was harder than before. It was easy to speak to him about school matters, but compliments? Feelings? Momo still couldn't completely believe that he had voted for _her_ of all people to be vice president.

Todoroki, as always, bluntly expressed himself. "It's the truth."

Momo felt her face flush. Desperately, she glanced out of the window before finding immense interest in packing up her belongings. Todoroki was silent as she grabbed her notebook and quickly stuffed it in her bag.

"I'm always worrying you, aren't I?" she rambled nervously, turning to face him while fiddling with her hands. At this rate, Momo might even accidentally create a few matryoshka dolls considering how jumpy she was. Her shoulders slumped as she mumbled ruefully, "As Class 1-A's vice president, I should be reassuring you, not the other way around…"

She trailed off, unsure of what to say next. Momo usually had no problem conversing with Todoroki: in fact, initial embarrassment and starstruck wonder aside, he was one of the people she enjoyed speaking with the most. Yet, for some reason, her extensive vocabulary abandoned her when her seatmate quirked a questioning, somewhat amused eyebrow at her.

"O-oh! I forgot to mention this yesterday, but the special effects at the concert yesterday were amazing!" she gushed, clapping her hands together in an attempt to hide the way her heart fluttered. Unfair...it was _unfair_ how Todoroki Shouto could throw her off her game with a small change of facial expression. "You and the others truly outdid yourselves. The crowd loved it."

"It was because of everyone's efforts." Todoroki's voice was lined with amusement. He offered her a hand, helping her out of her seat. "You and the band cheered them up, too."

"I'm glad that the audience enjoyed it," she admitted warmly. "Everyone worked so hard to make it special; it'll be hard to beat that next year."

"We'll come up with something," Todoroki stated confidently, sliding open the door and allowing her to pass first. She flashed him a grateful smile, exiting the classroom. They silently walked down the hallway side by side, matching their footsteps in perfect synchronicity. Momo was content with simply basking in the fire and ice user's presence, but to her surprise, he initiated a conversation.

"Yaoyorozu," he said suddenly, drawing her attention. "If there's something bothering you, you can always consult someone. Anyone in the class would be willing to help you."

Momo smiled faintly. "Does that _anyone_ include you, Todoroki-san?"

He blinked, then tilted his head and deadpanned, "Of course."

The sheer straightforwardness of Todoroki's statement had Momo reeling. She stared at him in surprise, which he took as confusion. "I simply considered the fact that you might feel comfortable sharing your troubles with one of your friends, so I didn't want to be upfront and offer my assistance," Todoroki explained, looking assured in his logic.

Momo blinked. Then, she blinked again. Finally, she doubled over, laughter escaping her lips before she could stop it. "Pfft...you're really something else, aren't you, Todoroki-san?" Momo giggled, her obsidian eyes shining with humor and genuine happiness. She straightened herself. "I...I don't mean to sound presumptuous, but I already consider you as one of my friends. Why did you think I would come along to rescue Bakugou-san?"

Todoroki ducked his head. "I thought it was because of your...obligations as vice president," he mumbled, his voice so quiet that Momo had to lean closer to hear him.

"As vice president, I _was_ concerned about you all," Momo confirmed, bobbing her head. "But if I was just Class 1-A's vice president, then I would have simply warned you and gone to the pro heroes to ensure that they would take every measure to keep you all safe. Instead, I chose to accompany you all. I did that because I consider you, Todoroki-san, and the rest of them as friends."

"...ah."

Some, at first glance, might say that Todoroki Shouto was just like his father; he had inherited the same (ironically enough) icy glare that Endeavor possessed, after all. But throughout their time together, Momo had discovered that Todoroki's cool countenance was nothing more than a result of his frankly pitiable social skills.

...and that was fine with her: she didn't mind filling in the gaps of the conversation.

"You seem surprised," Momo commented, raising an eyebrow at him.

"It's a...pleasant sort of surprised," Todoroki reassured her. "If it means anything at all, Yaoyorozu...I consider you my friend as well."

Warmth surged in her chest as they exchanged miniscule, silly smiles before continuing down the hallway, each highly aware of the other's presence.

And in that moment, Momo could almost completely forget about those chilly years of her youth.


	2. Chapter 2

Yaoyorozu was worried about something; Shouto could tell from the taut tenseness of her shoulders and the slight crease of her eyebrows. The raven-haired girl let out a weary sigh, rapping her fingers rhymatically on her desk. As Aizawa-sensei droned on and on about the various responsibilities of heroes, Shouto observed his seatmate with probing eyes.

Yaoyorozu was biting her lip again: it was a habit she often did when anxious about something, like an exam. (Personally, Shouto never understood _why_ she felt nervous before exams: Yaoyorozu consistently scored top in the class, a testament to her hardworking nature and commendable intellect.) Although her eyes remained firmly trained on the board, Yaoyorozu's mind was preoccupied with something other than their studies.

Shouto sighed, setting down his pencil. The bell rang, signalling the beginning of lunch. Immediately, students began streaming out into the hallways, chatter filling up the relative silence of the classroom. In the midst of it all, Shouto turned to her, expression placid. "Yaoyorozu," he called, drawing her attention before she could finish packing up her belongings.

The raven-haired girl blinked, setting down her bag and turning to face him. "Yes, Todoroki-san?" she asked, uncertain; although Shouto genuinely _enjoyed_ talking with Yaoyorozu, he rarely sought her out during lunch hours. The surprise that flashed across her features was warranted.

He bit the bullet: it was better for her to learn about it from _him_ than learn about it later herself.

"Do you need my notes?" Shouto gestured at his plain, royal blue notebook. He had never been one for elaborate, showy school supplies, especially not flammable ones. Sometimes, when he studied, Shouto would accidentally set the corners of his notebook on fire; he hoped that if she accepted his offer, Yaoyorozu would be kind enough to ignore the singe marks.

Confusion shone clearly in her eyes. "I'm afraid I don't understand what you mean, Todoroki-san," she apologized honestly.

"You were writing chemical formulas in your notebook the entire period," Shouto explained, gesturing to her violet notebook. Unlike the notebooks of his other female classmates, which proudly displayed all sorts of sparkly floral prints on the front covers, the only decoration on Yaoyorozu's notebook was an elegant fleur de lis. Shouto personally thought it suited her.

Yaoyorozu glanced down at her notebook, then let out a squeak of embarrassment. "Oh my, I didn't realize!" she gasped, wringing her hands nervously. She looked utterly mortified, red splaying across her cheeks. Hope danced in her eyes as she glanced at his notebook. "May I, Todoroki-san?"

Shouto inclined his head, handing it over without hesitation. "Of course." He paused, unsure of how to broach the subject. His movements languid, he crossed his arms over his chest, peering at her through his red-and-white bangs. "Is...is there something bothering you, Yaoyorozu?"

His seatmate hesitated, but caved under the weight of his heavy gaze. "It's just some silly nightmares," she admitted, averting her gaze. Her bangs fell before her face, shielding her expression from him. "Ever since the cultural festival finished without a hitch, I couldn't help but think that something might go wrong soon; we're always attracting so much trouble. A-ah, it's not like I _want_ anything to happen! It's just that my mind feels a bit uneasy…"

"I understand," Shouto responded unflinchingly.

"Y-you do…?"

"The League of Villains has been a bit too quiet lately," Shouto agreed, his eyes narrowing. "That can only spell trouble."

Yaoyorozu deflated, her shoulders sagging. "That's true, huh? Ah...I just hope our class won't be caught in the crossfire again…"

Shouto contemplated the notion for a sheer second before deadpanning, "Considering our previous encounters, that's doubtful."

Yaoyorozu laughed softly. "You really don't mince with your words...do you, Todoroki-san?"

He stared at her, wondering if he should have spoken more tactfully. Shouto was never particularly good at social niceties. "Am I not supposed to?"

"No, it's fine!" Yaoyorozu reassured him, waving her hands around frantically. Her voice rose in pitch. "I-it's something I admire about you, really! You always state your opinion as it is, regardless of what others think. I wish I can be that straightforward, but sometimes my nerves get the best of me."

Shouto frankly doubted that. Although the heroine-in-training tended to hesitate, she always came through when necessary. He opened his mouth, about to say as much, but was interrupted by the arrival of a familiar shock of emerald green hair.

"Say, Todoro—" Midoriya paused, then registered Yaoyorozu's presence. His eyes flickered back and forth between Shouto and Yaoyorozu for a few seconds before realization sunk into his features. "O-oh, am I interrupting something?"

"E-eh? No, not at all!" Yaoyorozu reassured him hastily, glancing at Shouto for validation. Her face was flushed again, for some reason. "Right, Todoroki-san?"

Shouto tilted his head. "Actually, we were in the middle of an important conversation, Midoriya," he responded, his voice somewhat monotonous. Out of the corner of his eye, he saw Yaoyorozu blush a bright, fire-engine red. When he caught her eyes, though, she quickly looked away.

Shoto frowned.

 _Strange. Did I say something wrong?_

" _Ohhh,_ I see." Midoriya nodded comprehendingly, shooting an apologetic smile at Yaoyorozu. He fidgeted awkwardly, then offered generously, "I'll go, then?"

Yaoyorozu's cheeks turned an even darker shade of scarlet. "I-it's not like that!" she defended, her voice strangled and unusually high-pitched. "We were just discussing a few matters. They aren't that important."

Shouto almost opened his mouth so say, " _But they're important to you, right?"_ At the last second, he decided against it, realizing that his seatmate was much too kind to worry others about her personal matters. Yaoyorozu wouldn't appreciate him spouting off her problems to the world.

Instead, he moved to face Midoriya; sometime during their conversation, he had shifted himself quite a bit so that he was facing Yaoyorozu completely. "Is something the matter?"

"No...it's just that...well, we were all sort of wondering if you were coming to lunch with us?" Midoriya gestured over towards the patiently waiting Iida and Uraraka. Shouto's eyebrows creased in confusion, then he turned to stare at the wall clock.

"Oops," slipped out of his lips before he could stop it. Immediately, he regretted it, glancing at a mortified Yaoyorozu.

"Oh my gosh, there's only ten minutes left?" Yaoyorozu realized at the same time he had. Immediately, she bowed a perfect ninety-degrees, clasping her hands together in apology. "I'm so sorry, Todoroki-san! I didn't mean to trouble you or the others," she rambled, then turned to Midoriya. "This was all my fault, Midoriya-san: please don't blame Todoroki-san. I'm extremely sorry…I'll definitely make it up to you..."

"I-it's fine!" Midoriya dismissed, obviously flustered by the girl's tearful apologies. "Please don't worry about it, Yaoyorozu-san. All of us have gotten distracted talking with someone at least once, you know? Time flies by when you're hanging out with someone you enjoy talking to."

Yaoyorozu stared at the green haired hero with such intensity that the boy (who had faced off plenty of Villains in his short time at Yuuei) squirmed. Then, a brilliant smile appeared on her face, lighting up her features. "That's a very astute observation, Midoriya-san!" she exclaimed cheerily, reinvigorated. "But as vice president, I should be more mindful of others' time, no? Todoroki-san, thank you very much for letting me express my grievances to you."

"I was happy to," Shouto mumbled under his breath, too quiet for her to hear. Midoriya, who caught the reply, beamed at him. Louder, Shouto replied, "Don't worry about it, Yaoyorozu."

"I'll return the notebook to you tomorrow morning," Yaoyorozu promised.

"Mm."

His seatmate didn't seem bothered by his succinct nature, bounding off with a wave and another deep bow. Shouto tilted his head, then turned to face Midoriya. The hero in training wore a goofy, wide smile as he stared at Shouto.

"...is something the matter, Midoriya?"

"O-oh? It's nothing!" he blabbered, sneaking a glance at Yaoyorozu's retreating figure. "Come on, let's hurry before lunch ends."

"...alright," Shouto allowed. Hopefully, Yaoyorozu would resolve whatever troubles were plaguing her. Just in case, though, he made a mental note to keep a closer eye on her as he followed Midoriya to lunch.

* * *

 **sobs you guys are too kind; also, these dorks are too cute**


End file.
